The overall purpose of this conference is to provide a forum for the exchange of ideas, information, and techniques in the area of non-ventilatory functions and properties of the lungs. The topics chosen for the 1980 Gordon Research Conference all focus on improving our understanding of the physiology and pathophysiology of lung injury. We are convinced that although the areas selected have been neglected they are now undergoing rapid and important change. The specific topics chosen include: 1) pulmonary cell renewal systems and their response to injury, 2) antigen and particulate transport through normal and injured epithelia, 3) molecular, electrolyte and water transport in normal and injured epithelia, 4) injury and repair of elastin, and 5) long term consequences of lung injury. Throughout the meeting there will be an emphasis on the similarities of the respiratory and gastrointestinal tracts and productive exchanges between basic scientists in these two areas are anticipated. This will constitute the fourth Gordon Research Conference on Non-Ventilatory Functions of the Lung. The first three have been outstanding successes; 62 scientists attended the first, and more than 100 attended the last two meetings. There is considerable evidence that this conference has developed into a significant continuing forum for communication among workers in this field and that it is an opportunity increasingly cherished by pulmonary biologists.